Repeat action for grand pianos



A ril 28, 1942. cQscHuLzE 2,280,982

REPEAT-ACTION FOR GRAND PIANQS Filed Feb. 3, 1941 Patented Apr. 28, 1942r UNITED STATES PATENT OFFICE This invention relates to a piano action,and while features of the invention may be adapted to different types ofaction, in the present specification the invention has been described asapplied to a grand piano action. In the grand type or square pianoaction, the hammer when at wardly from the hammer butt, and the hammerhead is located at a considerable horizontal distance from the pivotalsupport of the butt so that it is difficult to counterbalance the weightof the hammer head. Furthermore, this position of the hammer tends tocause it to return very rapidly to its normal position from the backcheck a problem is presented to counterbalance the hammer in such a waythat rapid repeat notes can be given. It is one of the objects of thisinvention to provide a construction which is particularly adapted forenabling rapid repeat notes to be struck. More specifically, theinvention concerns means which I employ for counterbalancing the weightof the hammer at the hammer butt in a way that will tend to retard thereturn of the hammer to its normal position if a key is struck and helddown, and then struck again to sound a repeat note. One of the objectsof the invention is to provide counterbalancing means which will applyits force in a follow-up manner to the hammer butt, and thereby give asuperior effect to an ordinary counterbalancing spring applied to thehammer butt, which must extend itself as the hammer moves forwardly, theresult of the extension of the spring being that it becomes relativelyweaker as a counterbalance spring in proportion to the degree of itsextension. In accordance with my invention the counterbalancing springoperates through a counterbalancing jack which is mounted on theactuating lever that actuates the 1 driving jack that drives the hammerin its stroke, thereby enabling the spring to exert a more or lessconstant counterbalancing effect even when the hammer is in itsadvanced, backcheck position.

A further object of the invention is to provide a piano action havingtheseadvantageous characteristics, composed of few parts and capable ofnice adjustment particularly as regards the degree of pressure orterbalancing jack.

Further objects hereinafter.

The invention consists in the novel parts. and combination of parts tobe described hereinafter,.

of the invention will appear thrust exerted by the counall of whichcontribute to produce an efficient repeat action for grand piano.

A preferred embodiment of the invention is described in the followingspecification, while the broad scope of the invention is pointed out inthe appended claims.

In the drawing:

Fig 1 is a vertical section through a piano case, certain parts beingbroken away, and illustrating the essential parts of a piano actionembodying my invention. In this view the action is shown in a positionof rest.

Fig. 2 is a view similar to Fig. 1, but shows the action in itsback-check position.

Before proceeding to a more detailed description of this piano action,it should be stated that in practicing the invention, an actuating leveris provided carrying a driving jack that cooperates with the drivingshoulder on the butt of the hammer. In addition to this, a resilientlypressed pivotal support for the hammer butt. In this way, as theactuating lever swings forwardly when the While the actuating leverreferred to in the above paragraph, may be actuated by the piano key, inthe simple construction illustrated in the drawing and now to bedescribed, the actuating lever is the rear end of the regular or usualpiano key.

' The key 9 which, of course, operates as an ac- 'tuating lever for theaction,

supports a regular jack H which is pivotally supported at l2 on a post Bor posts on the upper side of the key 9. I prefer, however, not tosupport the post l3 directly on the body of the key 9, but upon a splint9a which is virtually a part of the key but connected to the same by anysuitable means such as a screw 14. This construction is advantageousbecause it gives a ready vertical adjustment for the jack II, and alsofor the counterbalancing jack that will be presently described. Thisadjustment is made possible because the splint or tongue 9a adjacent itsroot I5, is cut down to a thin neck 16 which will readily flex, andunder the free end I! adjusting means is provided, enabling this freeend to be adjusted up or down. The resiliency of the splint 9a at theneck 16, tends to press the splint down toward the body of the key, andthis enables a very simple adjusting means to be employed, consisting ofone or more lifts or lift means I8 that may be put in position in thegap or throat 19 between the splint 9a and the body of the key.

This free end i! of the splint 9a constitutes a base means for resilientmeans to maintain the counterbalancing jack pressed against the butt 4of the hammer. In the present instance, for accomplishing my objects, Iprovide a leaf spring 20 which is disposed in an inclined position withits flat faces constituting its upper and lower sides. The relativelyfixed end of this spring may be held tight in a transverse inclined cut2| formed in the upper face of the base means H. The upper end of thespring 20 is preferably provided with a block 22 that affords means foreffecting a pivotal connection 23 to the lower end of a counterbalancingjack 24, the upper end of which thrusts against the under side of thebutt 4 at a bearing point that is located between the pivot of the buttand the driving shoulder 25, which is engaged by the toe of the jack II.In order to provide a slightly flexible connection between the upper endof the counterbalancing jack 24 and the bearing point for the jack onthe hammer butt, I prefer to provide a socket 26 on the under face ofthe butt 4, and I prefer to taper the upper end of the counterbalancingjack 24 and shape it sothat its upper end terminates in a pintle or pin21 that is of considerably smaller diameter than the socket 26, therebypermitting free movement at this point. The upper end of thecounterbalancing jack adjacent the pintle, is preferably in the form ofa tapered nose 28 with a slight shoulder at its upper end that thrustsagainst the pad 29 secured to the under side of the butt 4, includingthe edge of the socket.

This thrust and contact is preferably maintained throughout the entiremovement of the action. The jack I I is provided with the usual coilspring 38a under its heel 30, that presses the toe of the jack upagainst the driving shoulder 25. This driving shoulder 25, of course, ispadded and may have any desired form, but in the present instance it ,isshown. as an inclined shoulder that intersects with a substantiallyvertical shoulder 250:. When the action is at rest the spring 30a holdsthe toe of the jack up against this vertical rest shoulder 25a, that isto say, in the angle between this shoulder and the inclined shoulder 25.

When the key 9 is struck, the heel 30 of the jack encounters a set-offor stop 3| that swings the upper end of the jack out of engagement withthe shoulder 25 before the hammer 5 reaches the string. If the key isheld down, the hammer of course, will return to its back-check positionshown in Fig. 2. Now when a repeat note is struck, the release of thekey for striking the repeat note will, of course, permit the back-checkpad 1 to descend, and this, of course, would take it out of the path ofthe back-check tail 32 of the hammer head. The hammer would then beaccelerated downwardly by gravity, and in the absence of mycounterbalancing jack 24, this descent would be quite rapid and wouldnot allow time for the toe of the jack H to get back under the shoulder25 for striking a repeat note. However, my counterbalancing jack throughthe agency of-the leaf spring 20 that supports it, will exert aresistance that retards the fall of the hammer head 2, and this ofcourse, allows time for the jack II to get down under the shoulder 25 tostrike the repeat note or notes.

Attention is called to the fact that my improvement involves the basingof the counterbalancing jack spring 20 on the key 9 and between thelocation of the hammer butt and the fulcrum pin ID at which the key 9rocks. For this reason as the hammer butt 4 swings upwardly, the block22 that carries the counterbalancing jack 24, will have a considerablerise as it would move upwardly on a radius from the rocking point at thebase of the pin it up to the location of the conical tip'28.

As pointed out above, where it is necessary to makeany adjustment in theheight of this block 22, this can be accomplished by using thicker orthinner lifts l8 under the free end of the splint 9a. Some of theselifts may be of wood or rigid material, but it is advisable to have oneor more of these lifts composed of soft pad material such as indicatedin the drawing.

Many other embodiments of the invention may be resorted to withoutdeparting from the spirit of the invention.

What I claim is:

1. In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the'hammer butt, said butt having a drivingshoulder, an actuating lever, a driving jack pivotally supported on theactuating lever and engaging the driving shoulder for swinging thehammer forward, resilient means for pressing the driving jack, intocontact with the driving shoulder, set-off means cooperating withthe'jack' to move the same out of contact with the shoulder during theforward movement of the hammer, a resilient.counterbalancing membersupported on the actuating lever, a counterbalancing jack jointedthereto, engaging the hammer butt and maintaining contact substantiallyat all times with the same at a substantially fixed point on the. hammerbutt located between the driving shoulder and the pivotal support of thehammer butt, said counterbalancing jack operating to retard the returnof the hammer and thereby allow time after the actuating lever has beenmoved to, and held in, its extreme position, for the driving jack tore-engage with the driving shoulder, for strikinga repeat note.

2. In a piano action, hammer having a shank with a butt, a pivotalsupport for the hammer butt, said butt having a driving shoulder, anactuating lever, a driving jack pivotally supported on the actuatinglever and engaging the driving shoulder for swinging the hammer forward,resilientmeans for pressthe combination of a ing the driving jack intocontact with the driving shoulder, set-off means cooperating with thejack to move the same out of contact with the shoulder during theforward movement of the hammer, said butt having a bearing point locatedbe tween the driving shoulder and the hammers pivot, a counterbalancingjack for the hammer having a flexible joint supported on the actuatinglever, having a connection to, and thrusting against, the hammer butt atsaid bearing point, said counterbalancing jack operating to retard thereturn of the hammer and thereby allow time after the actuating leverhas been moved to, and held in, its extreme position, for the drivingjack to re-engage with the drivin shoulder, for striking a repeat note.

3. In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the hammer butt, said butt having a drivingshoulder, an actuating lever, a driving jack pivotally supported on theactuating lever and engaging the driving shoulder for swinging thehammer forward, resilient means for pressing the driving jack intocontact with the driving shoulder, set-off means cooperating with thejack to move the same out of contact with the shoulder during theforward movement of the hammer, a leaf-spring supported at one end onthe said actuating lever and having its free end located adjacent thehammer butt, a counterbalancing jack pivotally supported on the free endof the leaf spring, said hammer butt having a hearing point engaging theend of the countel-balancing jack and located between the drivingshoulder and the pivot point of the hammer butt.

4, In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the hammer butt, said butt having a drivingshoulder, an actuating lever, a driving jack pivotally supported on theactuating lever and engaging the driving shoulder for swinging thehammer forward, resilient means for pressing the driving jack intocontact with the driving shoulder, set-off means cooperating with thejack to move the same out of contact with the shoulder during theforward movement of the hammer, a leaf-spring supported at one end onthe said actuating lever and having its free end located adjacent thehammer butt, a counterbalancing jack pivotally supported on the free endof the leaf spring, said hammer butt having a bearing point engaging theend of the counterbalancing jack and located between the drivingshoulder and the pivot point of the hammer butt, the hammer butt havinga socket at the said hearing point, and-the counterbalancing jack havinga pin received loosely in the said socket to maintain the end of thecounterbalancing jack in contact with the hammer butt as it swingsforward.

5. In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the hammer butt, said butt having a drivingshoulder, an actuating lever, a driving jack pivotally supported on theactuating lever and engaging the driving shoulder for swinging thehammer forward, resilient means for pressing the driving jack intocontact with the dr iy ing shoulder, set-off means cooperating with thejack to move the same out of contact with the shoulder during theforward movement of the hammer, a counterbalancing leaf spring havingits free end located near the hammer butt carrying the relatively fixedend of the leaf spring and supported on the actuating lever so that thebase means is adjustable on the actuating lever to regulate the positionof the free end of the leaf spring, and a counterbalancing jacksupported on the free end of the counterbalancing leaf spring andthrusting against the hammer butt between its pivotal support and thedriving shoulder and operating to retard the return of the hammer, andthereby facilitate the playing of quick repeat notes.

6. In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the hammer butt, said butt having a drivingshoulder, an actuating lever, a driving jack pivotally supported on theactuating lever and engaging the driving shoulder for swinging thehammer forward, resilient means for pressing the driving jack intocontact with the driving shoulder, set-off means cooperating with thejack to move the same out of contact with the shoulder during a forwardmovement of the hammer, a splint connected with the actuating leveradjacent the free end of the lever, and extending under and past thehammer butt, lift means under the free end of the splint for adjustingthe same to any desired position, a counterbalancing leaf-springconnected to the free end of the splint, having its own free end lyingadjacent the hammer butt, and a counterbalancing jack having a pivotalconnection supporting the same on the free end of the counterbalancingspring and thrusting against the hammer butt between its pivotal supportand the driving shoulder, and operating to retard the return of thehammer to facilitate the playing of quick repeat notes.

7. In a piano action, the combination of a hammer having a shank with abutt, a pivotal support for the hammer butt, said butt having a drivingshoulder, a piano key having its fulcrum forward of the location of thehammer butt and with its rear end extending rearwardly under the hammer,a driving jack pivotally supported on the actuating lever and engagingthe driving shoulder for swinging the hammer forward, resilient meansfor pressing the driving jack into contact with the driving shoulder,set-01f means cooperating with the driving jack to move the same out ofcontact with the shoulder during the forward movement of the hammer, asplint supported on the rear end of the key and extending under and pastthe hammer butt, means associated with the free end of the splint foradjusting the same, a leaf-spring mounted on the free end of the splintwith its own free end lying adjacent to the hammer butt, said hammerbutt having a socket formed therein between the pivotal support of thehammer butt and the driving shoulder, a counterbalancing jack pivotallysupported on the free end of the leaf-spring and having its end receivedin the said socket, said counterbalancing jack operating to retard thereturn of the hammer and thereby facilitate the striking of rapid repeatnotes.

CARL SCHULZE.

